A western wildfire being fueled by strong winds and scorching temperatures has burned past firefighters' defenses and is menacing the city of Colorado Springs.

Firefighters battling the out of control blaze, which has grown to more than 15,000 acres, say they are bracing for worsening conditions.

"We expect further trouble from the weather today," Fire Incident Commander Rich Harvey said. "Thunderstorms present a unique problem for us. The wind can come in any direction from those ... at any time with pretty strong gusts."

About 1,000 firefighters are battling the Waldo Canyon blaze, which jumped to houses after getting refueled by 65 mph winds. About 32,000 people from Colorado Springs had to flee to safety. The fires are just 5 percent contained.

After flying over the area, Colorado Gov. John Hickenlooper compared it to the "worst movie set you could imagine."

"It's almost surreal," he told The Associated Press. "You look at that and it's like nothing I've seen before."

Three shelters have been opened for evacuees and residents were urged to remain inside because of the unhealthy air quality.

Evacuees who found themselves stuck in their cars used their clothes to shield their faces from the heavy smoke. Even some of the escape routes that residents planned to use were jammed with bumper-to-bumper traffic.

With the Fourth of July holiday approaching, authorities reminded residents to respect a ban on fireworks.

There were no reports of injuries or new evacuations and authorities said they had not yet determined the fire's cause despite reports of arson.

Dave Joly, a spokesman for the Denver FBI, said the agency was investigating whether the wildfires in Colorado Springs had resulted from criminal activity.

"FBI personnel are supporting command post operations in the fire regions and offering assistance with managing the volumes of information related to these tragic events," he said.

The windy weather and record heat hampered authorities' efforts to fight wildfires in the surrounding states as well. In addition to Colorado, Utah, Wyoming and Montana are under red-flag warnings, which warn of extreme fire danger.

One woman was found dead Tuesday after authorities revisited an evacuated area in Utah. Four homes were destroyed in northern Montana and a state of emergency was issued by the governor for four counties.